Since the ancient discipline with roots in Hinduism and Buddhism became a popular exercise in the West, yogis have inundated popular culture with their pursuit of that elusive “calm” in a rapidly spinning world.

“Mindfulness,” the meditative state associated with yoga, has likewise been adopted as a way to clear the mind.

So when administrators at Bullard Elementary School in Kennesaw, Ga., implemented yoga and other mindfulness practices in the classroom to reduce students’ stress, they probably envisioned peace and relaxation in their future.

Instead, they received a flurry of complaints — from parents who felt yoga represented the encroachment of non-Christian beliefs.